NAME

       ldd - print shared object dependencies

SYNOPSIS

       ldd [option]... file...

DESCRIPTION

       ldd  prints  the shared objects (shared libraries) required by each program or shared object specified on
       the command line.  An example of its use and output is the following:

           $ ldd /bin/ls
               linux-vdso.so.1 (0x00007ffcc3563000)
               libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f87e5459000)
               libcap.so.2 => /lib64/libcap.so.2 (0x00007f87e5254000)
               libc.so.6 => /lib64/libc.so.6 (0x00007f87e4e92000)
               libpcre.so.1 => /lib64/libpcre.so.1 (0x00007f87e4c22000)
               libdl.so.2 => /lib64/libdl.so.2 (0x00007f87e4a1e000)
               /lib64/ld-linux-x86-64.so.2 (0x00005574bf12e000)
               libattr.so.1 => /lib64/libattr.so.1 (0x00007f87e4817000)
               libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f87e45fa000)

       In  the  usual  case,   ldd   invokes   the   standard   dynamic   linker   (see   ld.so(8))   with   the
       LD_TRACE_LOADED_OBJECTS  environment  variable  set  to 1.  This causes the dynamic linker to inspect the
       program's dynamic dependencies, and find (according to the rules described  in  ld.so(8))  and  load  the
       objects  that satisfy those dependencies.  For each dependency, ldd displays the location of the matching
       object and the (hexadecimal) address at  which  it  is  loaded.   (The  linux-vdso  and  ld-linux  shared
       dependencies are special; see vdso(7) and ld.so(8).)

   Security
       Be  aware  that  in  some  circumstances (e.g., where the program specifies an ELF interpreter other than
       ld-linux.so), some versions of ldd may attempt to obtain the  dependency  information  by  attempting  to
       directly  execute  the  program,  which  may  lead  to  the  execution of whatever code is defined in the
       program's ELF interpreter, and perhaps to execution of the  program  itself.   (Before  glibc  2.27,  the
       upstream ldd implementation did this for example, although most distributions provided a modified version
       that did not.)

       Thus,  you  should never employ ldd on an untrusted executable, since this may result in the execution of
       arbitrary code.  A safer alternative when dealing with untrusted executables is:

           $ objdump -p /path/to/program | grep NEEDED

       Note, however, that this alternative shows only the direct dependencies  of  the  executable,  while  ldd
       shows the entire dependency tree of the executable.

OPTIONS

       --version
              Print the version number of ldd.

       --verbose
       -v     Print all information, including, for example, symbol versioning information.

       --unused
       -u     Print unused direct dependencies.  (Since glibc 2.3.4.)

       --data-relocs
       -d     Perform relocations and report any missing objects (ELF only).

       --function-relocs
       -r     Perform  relocations  for  both  data  objects  and  functions,  and report any missing objects or
              functions (ELF only).

       --help Usage information.

BUGS

       ldd does not work on a.out shared libraries.

       ldd does not work with some extremely old a.out programs which were built before ldd support was added to
       the compiler releases.  If you use ldd on one of these programs, the program will  attempt  to  run  with
       argc = 0 and the results will be unpredictable.

SEE ALSO

       pldd(1), sprof(1), ld.so(8), ldconfig(8)

Linux man-pages 6.9.1                              2024-05-02                                             ldd(1)